I have a paramagnetic powder sample dissolved in a solvent. The effect of diamagnetic solvent suppresses the signal of my paramagnetic complex going above 20 K. So I have only a measurement done at low temperature M vs H at constant temperature. Is there any way to calculate effective magnetic moment from this measurement?
what is the shape of MH at below 20 K? Are you sure that sample is paramagnetic at temperature below 20 K?
For the weak signals such as in paramaganetic compounds, the “demagnetization field contribution” which depends on the sample form must be taken into account.
Thus, for a spherical sample, the diagonal demagnetizing coefficient is Nd =1/3 and the effectif field is :Heff =Hex -Nd M, where Hex is the applied field, and the Heff is the effetcif field acting on the sample. M is the measured magnetization
M(emu/cm3) = 5.585*103 sigma*d/Mm,
Where
Mm =molar mass of the compound (g)
d =density (g/cm3)
sigma = magnetic moment in Bohr magnetron per molecule
Consequently you have : sigma (mB/molecule)= 10-3*M(emu/cm3)*Mm/5.585.d
Experimentally, You can estimate your saturation magnetic moment ss from the M(H) curves at low temperature by extrapolation of M(H) to H=0 (see fig in attached file)
The you can deduce the "gS" value via the relation sigmas = gmB S (1)
Where g is the Landé factor and mB is the Bohr magnetron
You can complete the calculation of both "spin S " and "g factor" if you have measured the magnetic susceptibility c(T) under a weak field up to higher tempertaures (in the paramagnetic regim) as follows :
Experimental data
T(K) : M(emu) : M(emu/mole) :c(T) = M/Heff : c corr(T) = c(T)-cd : 1/c corr
Here cd (cd
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